WASHINGTON (Reuters) - The United States has sent a Navy destroyer to patrol off the coast of Yemen to protect waterways from Houthi militia aligned with Iran, two U.S. officials told Reuters on Friday, amid heightened tension between Washington and Tehran.

The USS Cole arrived in the vicinity of the Bab al-Mandab Strait off southwestern Yemen where it will carry out patrols, including escorting vessels, the officials said, speaking on condition of anonymity.

In 2000, the USS Cole was attacked when al Qaeda bombers steered a boat full of explosives into the side of the American warship while it refueled in the Yemini port of Aden, killing 17 U.S. sailors and wounding about three dozen others.

While U.S. military vessels have carried out routine operations in the region in the past, this movement, first reported by Reuters, is part of an increased presence there aimed at protecting shipping from the Houthis, the officials said.

The Houthis are allied to Iran, which is at odds with the administration of U.S. President Donald Trump. The country recently test launched a ballistic missile.

Trump said on Thursday “nothing is off the table” in dealing with Iran, a day after his national security adviser, Michael Flynn said he was putting Iran “on notice.”

The officials said the decision to move the USS Cole was made before the most recent comments.

Earlier this week, the armed Houthi movement attacked a Saudi warship off the western coast of Yemen, causing an explosion that killed two crew members.

That incident was part of an escalation in combat on Yemen's western coast between the militia and the coalition backing the country's internationally recognized government.

Last October, the U.S. military launched cruise missile strikes to knock out three coastal radars located in areas of Yemen controlled by Houthi forces, retaliating after failed missile attacks on another U.S. destroyer, the USS Mason.

Tensions with Iran increased further on Friday when the U.S. Treasury Department announced sanctions on 13 people and 12 entities under U.S. Iran sanctions authority.